Tubular products (“tubulars”) are used in a variety of oilfield applications in which fluids are conveyed or isolated, and are found in both surface and downhole applications. Several hundred to several thousand feet of tubulars may be employed in such applications. Tubulars generally fall into two categories: continuous and jointed. Continuous tubulars are typically flexible and may be spooled or coiled for transportation and unspooled for use. Jointed tubulars are often more rigid. Rather than spooling, these tubulars may be provided in relatively short sections or “joints” and then connected together onsite for the application. When such tubulars are connected or “made up” together, they are often referred to as a “string” of tubulars. Casing and drill pipe are two examples of jointed tubulars that may be made into such strings.
In the oilfield, tubulars may be sufficiently robust to withstand high pressure differentials across their walls. Further, the tubulars may support tensile/compressive loads and/or torsional loads. In jointed tubular strings, the connection between the tubulars thus also supports such loads. A variety of such tubular connections or “couplings” have been designed and implemented for such loads.
However, these tubular couplings often call for complex designs and expensive specialty threading. Moreover, the couplings can represent a failure point in the tubular string. Thus, when the threads of the tubular itself, or of a coupling attached thereto, wear down, the affected tubulars and/or couplings may be replaced with a new assembly, which incurs the costs associated with replacing such parts.